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121.
Despite advances and improvements in diagnosis and treatment of upper aerodigestive tumors including head and neck and lung cancers, the overall survival rate of these patients remains poor. Prevention, early diagnosis, and novel therapy are under active investigation to improve the outcome of the diseases. In particular, chemopreventive strategy is a novel approach to reduce the invasive tumors by reversing the premalignant lesions with certain differentiating agents (i.e., retinoids). To conduct effective chemopreventive trials, there has been a great surge of interest in defining the biomarkers associated with the specific stages of the carcinogenesis and with intermediate end points during the therapy. Carcinogenesis in the upper aerodigestive tract has been explained by two theories, field cancerization and multistep process. The driving forces behind these processes are noted by accumulated genetic abnormalities in the entire epithelium of the airway. These genetic abnormalities include chromosome abnormalities, specific gene alterations (i.e., ras gene family, tumor suppressor genes, growth factors and their receptors), and proliferation and differentiation markers. These biomarkers are herein described in this review article.  相似文献   
122.
We examined the efficacy of two new preservation solutions containing trehalose-an extracellular type (ET-K) of solution and an intracellular type (IT-K) of solution — in relation to that of Euro-Collins (EC) solution in 20-h canine lung preservation. Canine lungs were flushed with one of the three solutions (n=5 for each solution) after pretreatment with PGE1 (20 g/kg) and were stored for 20 h at 4°C. The left lungs were transplanted and evaluated to 6 h post transplant. In the ET-K group, the arterial oxygen tension after reperfusion was significantly higher than in the IT-K and EC groups. The pulmonary vascular resistance, wet/dry weight ratio, and histological evaluation of each transplanted lung in the ET-K group were also better than in the IT-K and EC groups. This indicates that ET-K solution is useful for 20-h preservation of canine lung grafts.  相似文献   
123.
Long-term outcome in 134 patients with galactosaemia   总被引:6,自引:0,他引:6  
In a retrospective study 134 galactosaemic patients, born between 1955 and 1989 in the Federal Republic of Germany were traced and their long-term outcome evaluated. We investigated 83 galactosaemic patients (78 homozygotes, 5 compound heterozygotes) by clinical, psychometric and laboratory testing; 31 patients were evaluated by medical history, the remaining 20 patients had died due to sequelae of the underlying disease. In 48 out of 78 classical galactosaemia patients galactose-free therapy had been started before the 15th day, in 19 between days 15 and 56 and in 11 patients after the 56th day. Physical findings revealed that puberty was delayed in 1 out of 18 males and 6 out of 11 females. Neurological abnormalities included ataxia (n=6), intention tremor (n=11) and microcephaly (n=10). Speech abnormalities were found in 43 out of 66 patients over 3 years of age and disturbance of visual perception and/or arithmetic deficits in 29. Intelligence declined with age, i.e., a DQ or IQ less than 85 was found in 4 out of 34 patients less than 6 years of age (12%), in 10 out of 18 between 7 and 12 years (56%) and in 20 out of 24 older than 12 years (83%). Metabolite patterns (RBC galactose-1-phosphate and UDP-galactose, plasma and urinary galactitol) did not correlate with DQ or IQ. Dietary compliance was good in almost all patients. Compound heterozygotes (n=5) had normal mental and growth development and all laboratory parameters were in the normal range. The cause of the unsatisfactory outcome of well-treated galactosaemic patients with disturbances in long-term development remains unclear. This could be due to a chronic intoxication of galactose metabolites or a deficiency of UDP-galactose or galactose-containing glycoproteins or glycolipids.This study was supported by a grant from the Stifterverband für die Deutsche Wissenschaft (Huebner-stiftung), grant TS 114/18/89 and by the Arbeitsgemeinschaft für Pädiatrische Stoffwechselstörungen  相似文献   
124.
Angiographic study of the motion of the septal and left marginal arteries was performed in patients with restriction in ventricular diastolic filling in order to separate patients with constrictive pericarditis from those with restrictive cardiomyopathy. Twelve patients with constrictive pericarditis (group I) and 10 patients with restrictive cardiomyopathy (group II) were evaluated and compared with 21 patients with normal coronary angiograms (group III). The displacement of the septal arteries (23 +/- 2.04 mm) was abnormally exaggerated in group I and normal (9 +/- 0.81 mm) in groups II and III. The displacement of the left marginal arteries as seen by the "corrugating index" was similar in all groups. We conclude that study of the displacement of the septal arteries is a useful angiographic sign that helps to separate constrictive pericarditis from restrictive cardiomyopathy and normals.  相似文献   
125.
Analysis of particle size distribution of a sample of fine aluminum hydroxide powder was carried out by four different methods,i. e., conductivity, air permeability, gas-adsorption and sedimentation. Each method was reproducible. The results obtained by Coulter counter and sedimentation balance were similar, and the data obtained by Lea and Nurse permeameter and Stroehlein areameter were also similar. But the results differ considerably between the former and the latter. The advantages and disavantages of each method were discussed briefly and a means of comparing the results with those obtained by surface area measurements was shown.  相似文献   
126.
Summary Fourteen patients previously treated with surgery, radiotherapy, and/or chemotherapy for primary squamous cell carcinoma of the head and neck were treated with 4-O-tetrahydropyranyl-Adriamycin (THP-adriamycin) for locally or distantly recurrent disease. The starting dose was 60 mg/m2 by i.v. infusion, with courses repeated every 3 to 4 weeks. A total of 34 courses of treatment were delivered (median, 2; range, 1–6). All patients were evaluable for response and toxicity. There were no responses. Severe (grade 3 or 4) neutropenia occurred in 11 patients. Thrombocytopenia, anemia, and gastrointestinal toxicity were modest, and no hepatic, renal, or cardiac toxicity was observed. The lack of response in association with severe neutropenia and moderate other toxicities using this dose and schedule of THP-Adriamycin should be taken into consideration prior to the pursuit of further study of this compound in a similar patient population.  相似文献   
127.
Corneal permeability of variousn-alkylp-hydroxybenzoates (parabens) was studiedin vitro using excised rabbit corneas, and the effect of lipophilicity of parabens on the corneal permeability was also investigated. Permeability coefficients were obtained from the least-square linear regression after the steady state had been reached. Lipophilicity of parabens was calculated by distribution coefficients determined in octanol-S \(12_\phi [\kern-0.15em[ \) rensen’s buffer solution (pH 5.0). The relationship between lipophilicity and corneal permeability of parabens was not linear, but the optimum lipophilicity for the maximum permeation was found. The influence of tween 80 on corneal permeability of methyl and butylparaben was not significant.  相似文献   
128.
蝙蝠葛中的新生物碱——蝙蝠葛新林碱   总被引:3,自引:0,他引:3  
防已科植物蝙蝠葛(Menispermum daurioum DC.)的根茎,即北豆根,是一种重要的中药,具有清热解毒、消肿止痛等功效。已知含有近二十种生物碱,其中五种属双苄基四氢异喹啉类,即蝙蝠葛碱(dauricine,Ⅰ)、蝙蝠葛诺林碱(daurinoline,Ⅱ)、蝙蝠葛新诺林碱  相似文献   
129.
Sevoflurane was compared to isoflurane anesthesia alone and in combination with atracurium or vecuronium in 84 rats using the sciatic nerve—anterior tibialis muscle preparation. Both bolus injection and infusion rate techniques were used to evaluate these drug interactions. The ED50 (dose which produced a 50% depression of twitch tension) of atracurium was 311 ± 31 and 360 ± 32µg·kg–1 during 1.25MAC sevoflurane and isoflurane anesthesia respectively. The ED50 of vecuronium was 190 ± 27 and 149 ± 14µg·kg–1 during 1.25MAC sevoflurane and isoflurane anesthesia respectively. The mean infusion rates of atracurium and vecuronium required to maintain a 50% depression of twitch tension were 5.04 ± 0.7 and 2.02 ± 0.3mg·kg–1·hr–1. These infusion rates were 5.04 ± 0.7 and 2.02 ± 0.3mg·kg–1·hr–1 during 1.25MAC sevoflurane and 3.73 ± 0.3 and 1.81 ± 0.4mg·kg–1·hr–1 during 1.25MAC isoflurane anesthesia respectively. With both atracurium and vecuronium, the infusion rate required to maintain a 50% depression twitch of tension was inversely related to the concentrations of isoflurane and sevoflurane. The authors conclude that sevoflurane is similar in potency to that of isoflurane in augmenting a vecuronium or atracurium induced neuromuscular blockade in a dose-dependent manner.(Shin YS, Miller RD, Caldwell JE, et al.: The neuromuscular effects of sevoflurane and isoflurane alone and in combination with vecuronium or atracurium in the rat. J Anesth 6: 1–8, 1992)  相似文献   
130.
We programmed a formula which predicts the incidence of either myocardial infarction or cardiac death during the postoperative period. The original formula was proposed by Shah et al, based on their own data and analysis. The program is simple and is written in a language called Quick Basic. The use of this program is also simple. Such a program has improved the use of this analysis substantially. The program has been posted on to a few Computer network services as a free software.(Suwa K, Ogura S: Programming a predictive formula for angina and other risk factors in patients with cardiac diseases undergoing non-cardiac operations. J Anesth 6: 241–242, 1992)  相似文献   
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